Typical sighting or targeting reticles generally comprise a circular sighting ring with a central cross-hair or “pipper” which marks the exact aiming-point or target at within the field of view of the sighting ring. FIG. 1 illustrates a simple example of the basic reticle symbology of the prior art.
Sighting reticles may be adequate for gun sighting or camera-aiming purposes, particularly when the associated device (e.g. the gun or the camera) maintains a fixed orientation with respect to an operator. The situation becomes more complex however, when the frame of reference is no longer fixed. This situation occurs for example with a turret-mounted device which incorporates two or more axes of rotational freedom compared to a position of the operator. The most complex level of abstraction arises when the operator is no longer located in an aiming vehicle, as is the case for example with Unmanned Aerial Vehicles (UAVs).
In controlling UAVs for example, the operator lacks all non-instrument cues regarding the orientation and flight path of the vehicle, which makes it extremely challenging for a sensor operator to remain oriented in space. When a target of interest (TOI) or a “threat” is identified on the camera image, it is extremely difficult for the operator to determine which direction the vehicle should be turned to intercept, photograph, or evade the “threat”. Some systems use auto-stabilization and auto-tracking devices to diminish the adverse effects by maintaining a “lock” on the target using gimballing techniques. These techniques however add yet another level of abstraction outside the operator's control loop for the vehicle and its sighting system.
There is therefore a need to provide a sighting reticle which aids an operator in controlling the vehicle.